The marks, which can be read only under ultraviolet light, will mean police can trace where any alcohol seized was bought. Wine, vodka, cider and alcopops will be targeted.
Botterill's Armadale store is one of the latest to sign up. Operations director Brian Straiton said: "We were very willing to get involved. It's important to work with the authorities so that the unscrupulous retailers can be rooted out."